Method and apparatus to manage power consumption of a semiconductor device

ABSTRACT

Briefly, a method an apparatus of a power management system of a semiconductor device capable of managing a power consumption of the semiconductor device by varying an operating voltage of the semiconductor device according to a voltage value based on a reference number.

CROSS-REFERENCE TO RELATED APPLICATIONS

This present application is a continuation of U.S. Pat. No. 7,379,718issued May 27, 2008 titled “METHOD AND APPARATUS TO MANAGE POWERCONSUMPTION OF A SEMICONDUCTOR DEVICE.” The specification of said patentis hereby incorporated in its entirety, except for those sections, ifany, that are inconsistent with this specification.

BACKGROUND OF THE INVENTION

Semiconductor devices are commonly referred to in the art as “chips”.Some semiconductor devices may include micro-electronic systems. Forexample, a system-on-chip (SOC) may include a graphic controller, aprocessor, a modem, one or more wireless communication units, aninput/output interface unit, a display controller, a digital signalprocessor, one or more memories, or the like. Systems-on-chip may beused, for example, in battery operated devices and/or low power devices,and may include a dynamic voltage management (DVM) mechanism to controla power consumption of system-on-chip or other elements of the batteryoperated and/or low power device.

BRIEF DESCRIPTION OF THE DRAWINGS

The subject matter regarded as the invention is particularly pointed outand distinctly claimed in the concluding portion of the specification.The invention, however, both as to organization and method of operation,together with objects, features and advantages thereof, may best beunderstood by reference to the following detailed description when readwith the accompanied drawings in which:

FIG. 1 is a schematic illustration of a wireless communication deviceaccording to exemplary embodiments of the present invention;

FIG. 2 is a schematic block diagram of a power management systemaccording to exemplary embodiments of the invention;

FIG. 3 is a schematic flowchart of a method to vary an operating voltageof a semiconductor device according to one exemplary embodiment of theinvention; and

FIG. 4 is a schematic flowchart of a method to vary an operating voltageof a semiconductor device according to another exemplary embodiment ofthe present invention.

It will be appreciated that for simplicity and clarity of illustration,elements shown in the figures have not necessarily been drawn to scale.For example, the dimensions of some of the elements may be exaggeratedrelative to other elements for clarity. Further, where consideredappropriate, reference numerals may be repeated among the figures toindicate corresponding or analogous elements.

DETAILED DESCRIPTION OF THE INVENTION

In the following detailed description, numerous specific details are setforth in order to provide a thorough understanding of the invention.However it will be understood by those of ordinary skill in the art thatthe present invention may be practiced without these specific details.In other instances, well-known methods, procedures, components andcircuits have not been described in detail so as not to obscure thepresent invention.

Some portions of the detailed description, which follow, are presentedin terms of algorithms and symbolic representations of operations ondata bits or binary digital signals within a computer memory. Thesealgorithmic descriptions and representations may be the techniques usedby those skilled in the data processing arts to convey the substance oftheir work to others skilled in the art.

Unless specifically stated otherwise, as apparent from the followingdiscussions, it is appreciated that throughout the specificationdiscussions utilizing terms such as “processing,” “computing,”“calculating,” “determining,” or the like, refer to the action and/orprocesses of a computer or computing system, or similar electroniccomputing device, that manipulate and/or transform data represented asphysical, such as electronic, quantities within the computing system'sregisters and/or memories into other data similarly represented asphysical quantities within the computing system's memories, registers orother such information storage, transmission or display devices. Inaddition, the term “plurality” may be used throughout the specificationto describe two or more components, devices, elements, parameters andthe like. For example, “plurality of mobile stations” describes two ormore mobile stations.

It should be understood that the present invention may be used in avariety of applications. Although the present invention is not limitedin this respect, the circuits and techniques disclosed herein may beused in many apparatuses such as, for example a hand held devices,battery operated devices wireless communication devices of a radiosystem and the like. Wireless communication devices intended to beincluded within the scope of the present invention include, by way ofexample only, wireless local area network (WLAN) devices, two-way radiodevices, digital radio devices, analog radio devices, cellularradiotelephone devices and the like.

Types of hand held devices intended to be within the scope of thepresent invention include, although are not limited to, tabletcomputers, personal data assistance (PDA), portable electronic mail(Email) device, or the like.

Some embodiments of the invention may be implemented, for example, usinga machine-readable medium or article which may store an instruction or aset of instructions that, if executed by a machine (for example, bystations of wireless communication system, and/or by other suitablemachines), cause the machine to perform a method and/or operations inaccordance with embodiments of the invention. Such machine may include,for example, any suitable processing platform, computing platform,computing device, processing device, computing system, processingsystem, computer, processor, or the like, and may be implemented usingany suitable combination of hardware and/or software. Themachine-readable medium or article may include, for example, anysuitable type of memory unit, memory device, memory article, memorymedium, storage device, storage article, storage medium and/or storageunit, for example, memory, removable or non-removable media, erasable ornon-erasable media, writeable or re-writeable media, digital or analogmedia, hard disk, floppy disk, Compact Disk Read Only Memory (CD-ROM),Compact Disk Recordable (CD-R), Compact Disk Rewriteable (CD-RW),optical disk, magnetic media, various types of Digital Versatile Disks(DVDs), a tape, a cassette, or the like. The instructions may includeany suitable type of code, for example, source code, compiled code,interpreted code, executable code, static code, dynamic code, or thelike, and may be implemented using any suitable high-level, low-level,object-oriented, visual, compiled and/or interpreted programminglanguage, e.g., C, C++, Java, BASIC, Pascal, Fortran, Cobol, assemblylanguage, machine code, or the like.

Turning to FIG. 1, a wireless communication device 100 in accordancewith exemplary embodiments of the invention is shown. Although the scopeof the present invention is not limited in this respect, wirelesscommunication device 100 may be a cellular mobile device, a wirelessdevice of a wireless local area network (WLAN) and/or a wirelessmetropolitan area network (WPAN) such as, for example, an access point,a wireless personal digital assistant (PDA), a mobile computer, a mobiledata terminal, and the like.

According to the exemplary embodiment shown in FIG. 1, wirelesscommunication device 100 may include an antenna 110, a semiconductordevice 120, a display 130, a speaker 140, a microphone 150, a voltageregulator 160, a power source 160, and a keyboard 180, although thescope of the present invention is in no way limited to this exemplaryembodiment of the invention.

Although the scope of the present invention is not limited in thisrespect, in some embodiments of the invention, semiconductor device 120may include a system on chip (SOC), which may be capable of performingat least some tasks of a mobile communication device. For example,semiconductor device 120 may include a wireless communication unit 121capable of operating in a cellular radiotelephone system and/or in aWLAN and/or in a WPAN and/or in piconets and/or in other like systems ornetworks. In addition, semiconductor device 120 may include a processor122, a memory 123, an input/output (I/O) interface unit 124, a powermanagement unit 125, an audio/video unit 126, a display controller 127and a frequency generator 128.

Although the scope of the present invention is not limited in thisrespect, antenna 110 may include one or more antennas and the antennasmay include an internal antenna, an antenna array, a dipole antenna, amulti-poles antenna, a multi directional antenna or the like. In someembodiments of the invention, antenna 110 may be operably coupled to thewireless communication unit 121 and may receive and/or transmitmodulated radio frequency (RF) signals. Processor 122 may include adigital signal processor (DSP) and/or other type of processor and may beoperably connected by a bus 129 to the other units of semiconductordevice 120, if desired.

In some exemplary embodiments of the present invention, I/O interfaceunit 124 may be operably coupled to keyboard 180 and may transferkeyboard strokes to processor 122, if desired. Memory 123 may include aFlash memory and/or any other desired type of memory and may be capableof storing applications, operating systems, temporary data values or thelike. Audio/Video unit 126 may be coupled to loudspeaker 140 andmicrophone 150 and may process audio signals. In addition, in some otherembodiments of the invention audio/video unit 126 may include a graphicprocessor and may be coupled to a camera or video camera (not shown) andmay be able to process images and/or video which may be displayed ondisplay 130, if desired. Display controller 127 may control display 130,which may include a liquid crystal display and/or any other type ofgraphic or alphanumeric display, if desired.

Although the scope of the present invention is not limited in thisrespect, frequency generator 128 may generate a desired clock frequencyof semiconductor device 120. According to some embodiments of theinvention the clock frequency may be varied to control a powerconsumption of semiconductor device 120. Power management unit 125 mayreceive from bus 129 a reference number, which may be related to theclock frequency and may be used as a basis for varying an operatingvoltage of semiconductor device 120 by converting the reference numberto a voltage value. Power management unit 125 may provide the voltagevalue to voltage regulator 160 which may set the voltage ofsemiconductor device 120 according to this value, if desired.

Although the scope of the present invention is not limited in thisrespect, in some embodiment of the invention semiconductor device 120may include a software and/or hardware and/or any combination ofhardware and software that may translate a required operating frequencyof the semiconductor device 120 into corresponding reference numbersrelated to a required operating frequency and/or a required operatingvoltage level of the semiconductor device. The reference numbers may befurther manipulated by software and/or hardware and/or any combinationof hardware and software to provide a required voltage value, ifdesired.

Turning to FIG. 2, a block diagram of a portion of a power managementsystem 200 according to an exemplary embodiment of the invention isshown. Although the scope of the present invention is not limited inthis respect, power management system 200 may be capable of controllingpower consumption of semiconductor device 120. In this exemplaryembodiment of the invention, power management system 200 may beimplemented within semiconductor device 120. It should be understoodthat power management system 200 may be implemented by hardware and/orsoftware and/or any suitable combination of hardware and software.

Although the scope of the present invention is not limited in thisrespect, power management system 200 may include one or more frequencycontrol registers 220, which may control an operating frequency ofsemiconductor device 120; one or more mapping registers 230, which maymap a frequency range to a voltage level; one or more voltage settingregisters 240, which may set the voltage level to a voltage value; avoltage level decoder 250; a voltage value decoder 260; and a powermanagement unit 270.

Although the scope of the present invention is not limited to thisrespect, it should be understood that in some embodiments of the presentinvention, memories and/or look up tables and/or a software functionsand/or hardware units and the like may be used to fulfill functions offrequency control registers 220, mapping registers 230 and voltagesetting registers 240, although the scope of the present invention isnot limited in this respect.

Although the scope of the present invention is not limited in thisrespect, in some embodiments of the invention, a bus 280 may providevalues from different units of semiconductor device 120 to registers220, 230 and 240. For example, processor 122 of FIG. 1 may provide arequired operating frequency value to frequency control registers 220.Frequency control registers 220 may provide the required operatingfrequency value to frequency generator 128, which may set the requiredoperating frequency of semiconductor device 120. In addition, frequencycontrol registers 220 may provide the required operating frequency valueto power management unit 270 and to decoder 250.

Additionally or alternatively, the semiconductor device may include twoor more processors and/or other units that may require differentoperating frequencies, which may be provided to frequency controlregisters 220, if desired.

According to one exemplary embodiment of the invention, processor 122may provide a range of frequency values to mapping registers 230.Mapping registers 230 may map a range of frequency values to a requiredvoltage level. For example, the required voltage level value may be areference number related to a voltage level, e.g., high, medium or lowvoltage levels. In another exemplary embodiment, the reference numbermay be related to first, second, third, forth voltage level and thelike. Mapping registers 230 may match between a range of frequencies andthe reference number that relates to the voltage level, if desired.Voltage level decoder 250 may assign a reference number to the requiredvoltage level according to the required operating frequency.

Although the scope of the present invention is not limited in thisrespect, setting registers 240 may match one or more voltage values tothe required voltage level and may provide a matched voltage value tovoltage value decoder 260, if desired. Voltage value decoder 260 maydecode the required voltage value from the reference number (e.g. therequired voltage level) and the matched voltage value. According to someembodiments of the invention, power management unit 270 may receive therequired voltage and the required operating frequency and may set anexternal voltage regulator (e.g. voltage regulator 160) to provide therequired voltage to semiconductor device 120.

Although the scope of the present invention is not limited in thisrespect, for example, an operating voltage range of semiconductor devicemay include a sub-range of a 0.5V to 1.8V range. An operating frequencyrange may vary, e.g., from a few MHz to about one Gigahertz, if desired.In some embodiments of the invention, the power may be calculatedaccording to the formula ½*C*V²*F, where C may be the chargedcapacitance on every toggle of a gate of semiconductor device 120, V mayrepresent a supply voltage of semiconductor device 120 and F mayrepresent an operating frequency, although the scope of the presentinvention is not limited in this respect.

According to some other embodiments of the present invention, afrequency controller 290 may provide a required frequency value tofrequency control registers 220 (shown with dotted line). Frequencycontroller 290, which may include a hardware unit, may monitor the powerconsumption of units and/or components and/or cores of semiconductordevice 120, and may vary frequencies of those units and/or componentsand/or cores to the required frequency, although the scope of thepresent invention is not limited in this respect.

In addition, a monitor 295 (shown with dotted line) may monitor atemperature of the semiconductor device, a process skew or any otherproperty that may be determined, e.g., automatically, by circuits of thesemiconductor device. Monitor 295 may provide indications of themonitored properties to decoder 260 which may decode the requiredvoltage value according to the required voltage level. Voltage valuedecoder 260 may be capable of manipulating a reference number with theone or more monitored properties, although the scope of the presentinvention is not limited in this respect.

Turning to FIG. 3, a flowchart of a method to vary an operating voltageof a semiconductor device according to exemplary embodiments of thepresent invention is shown. Although the scope of the present inventionis not limited in this respect, for example, power management system 200may employ one or more methods and/or algorithms and/or mechanisms tovary the operating voltage of semiconductor device 120, if desired.

According to one embodiment of the invention, power management system200 may receive a required voltage level e.g., from decoder 250 (textblock 300). For example, the request may come when for example, anoperating frequency have been changed, or if one or more environmentalparameters such as, for example a temperature has been changed (textblock 310). The required voltage value may be determined, for example,by decoder 260 (text block 320), and power management unit 270 may drivea voltage change sequence to be executed by an external voltageregulator, for example, voltage regulator 160 of FIG. 1, if desired(text block 330).

Turning to FIG. 4, a flowchart of a method to vary an operating voltageof a semiconductor device according to another exemplary embodiment ofthe present invention is shown. Although the scope of the presentinvention is not limited in this respect, the semiconductor device mayinclude a system on a chip, for example, on semiconductor device 120 ofFIG. 1. Furthermore, the semiconductor device may include a processor(e.g. processor 122) that may operate a software application to controlpower consumption characteristics of the semiconductor device (e.g.semiconductor device 120). In one embodiment of the invention, thesoftware application may request a frequency change and, in someembodiments of the invention, a frequency change request may be made byhardware, if desired (text block 400). A power management system of thesemiconductor device may determine if the required frequency change maybe higher then an operating frequency of the semiconductor device (textblock 410). For example, in some embodiments of the invention thesoftware may use frequency control registers (e.g. frequency controlregisters 220) to vary the frequency, if desired.

According to some embodiments of the invention, the power managementsystem may determine the required voltage level (text box 420) and, ifthe required voltage level is higher then a current voltage level (textbox 430), the software and or the hardware may call a voltage changetask (text box 430). For example, in some embodiments of the inventionthe voltage change task may control a power management unit (e.g. powermanagement unit 270) to change the voltage of the semiconductor device.In this exemplary embodiment of the invention, the method may end bychanging the operating frequency of the semiconductor device to therequired frequency (text box 450). For example, the software applicationmay set frequency generator 128 of FIG. 1 to the required frequency, ifdesired.

Although the scope of the present is not limited to this exemplaryembodiment of the invention, the required frequency may be lower thanthe operating frequency (text box 410) and the software may change theoperating frequency to the required frequency (text box 460). Accordingto this embodiment of the invention, the required frequency level may belower then the current frequency level (text box 480) and the softwaremay call the voltage change task to change the voltage of thesemiconductor device according to the required voltage level (text box490). In some embodiments of the invention the voltage change task maywait for an acknowledge (ACK) signal from the power management unit(e.g. power management unit 220) as is shown in text blocks 440 and 450although the scope of the present invention is not limited in thisrespect.

While certain features of the invention have been illustrated anddescribed herein, many modifications, substitutions, changes, andequivalents will now occur to those skilled in the art. It is,therefore, to be understood that the appended claims are intended tocover all such modifications and changes as fall within the true spiritof the invention.

1. A method for setting an operating frequency and an operating voltageof a semiconductor device, wherein the operating voltage of thesemiconductor device is set by a voltage regulator that is external tothe semiconductor device, the method comprising: monitoring a propertyof the semiconductor device; setting the operating frequency of thesemiconductor device at a first frequency value; and translating thefirst frequency value into a voltage level, wherein the voltageregulator generates the operating voltage for the semiconductor devicebased on i) the first frequency value and ii) the voltage level, andwherein the translating the first frequency value into the voltage levelcomprises assigning a reference number to the first frequency value,manipulating the reference number based on the monitored property of thesemiconductor device, and converting the manipulated reference numberinto the voltage level.
 2. The method of claim 1, wherein monitoring theproperty of the semiconductor device comprises monitoring a temperatureof the semiconductor device.
 3. The method of claim 1, whereinmonitoring the property of the semiconductor device comprises monitoringa process skew of the semiconductor device.
 4. The method of claim 1,wherein: setting the operating frequency of the semiconductor device atthe first frequency value comprises setting a component of thesemiconductor device to operate at the first frequency value; and thevoltage regulator is configured to generate the operating voltage forthe component of the semiconductor device.
 5. The method of claim 1,wherien the component of the semiconductor device is one or more of aprocessor, a modem, a graphic controller, a wireless communication unit,a display controller, a digital signal processor, and a memory.
 6. Asemiconductor device comprising: a power management unit capable ofmanaging a power consumption of a semiconductor device by varying anoperating voltage of the semiconductor device according to a requiredvoltage value based on a reference number, wherein the reference numberis related to one or more voltage levels; and a voltage level decoder todecode a required voltage level and an operating frequency of thesemiconductor device to provide the reference number.
 7. Thesemiconductor device of claim 6, wherein the voltage level decoder iscapable of decoding the required voltage level and operating frequenciesof two or more units of the semiconductor device to provide thereference number.
 8. The semiconductor device of claim 7, wherein thevoltage level decoder is capable of manipulating the reference numberwith a property of the semiconductor device to provide the requiredvoltage value.
 9. The semiconductor device of claim 6, furthercomprising: a voltage value decoder to decode the reference number andto produce the required voltage value according to the required voltagelevel.
 10. An apparatus comprising: a power management unit configuredto vary a voltage of the apparatus according to a required voltage valuerelated to a reference number based on a required voltage level, whereinthe required voltage level is related to a required operating frequencyof the apparatus; one or more frequency control registers to provide arequired operating frequency value; and a voltage level decoder toassign the reference number to the required operating frequency value.11. The apparatus of claim 10, further comprising: one or more settingregisters to match one or more voltage values to the required voltagelevel to provide a matched voltage value; and a voltage value decoder todecode the required voltage value from the reference number and thematched voltage value.
 12. The apparatus of claim 11, wherein thevoltage value decoder is capable of manipulating the reference numberwith one or more properties of the apparatus to produce the requiredvoltage value.
 13. A hand held device comprising: a voltage regulator toprovide a voltage value of a semiconductor device; one or more frequencycontrol registers to provide a required operating frequency value; and avoltage level decoder to assign a reference number to a required voltagelevel according to the required operating frequency value; wherein thesemiconductor device includes a power management unit configured to varya voltage of the voltage regulator according to a required voltage valuerelated to the reference number based on the required voltage level; andwherein the required voltage level is related to a required operatingfrequency of the apparatus.
 14. The hand held device of claim 13,wherein the semiconductor device further comprises: one or more settingregisters to match one or more voltage values to the required voltagelevel to provide a matched voltage value; and a voltage value decoder todecode the required voltage value from the reference number and thematched voltage value.
 15. The hand held device of claim 14, wherein thevoltage value decoder is capable of manipulating the reference numberwith one or more properties of the semiconductor device to produce thevoltage value.
 16. An apparatus comprising: a semiconductor device,wherein the semiconductor device includes a monitor configured tomonitor a property of the semiconductor device, a frequency generatorconfigured to set an operating frequency of the semiconductor device ata first frequency value, a mapping register configured to translate thefirst frequency value into a reference number, wherein the referencenumber corresponds to a voltage level; and a voltage regulatorconfigured to generate an operating voltage for the semiconductor devicebased on i) the first frequency value and ii) the voltage level, whereinthe semiconductor device further comprises a voltage decoder configuredto manipulate the reference number based on the monitored property ofthe semiconductor device.
 17. The apparatus of claim 16, wherein theproperty of the semiconductor device corresponds to a temperature of thesemiconductor device.
 18. The apparatus of claim 16, wherein theproperty of the semiconductor device corresponds to a process skew ofthe semiconductor device.
 19. The apparatus of claim 16, wherein thesemiconductor device comprises one or more of a processor, a modem, agraphic controller, a wireless communication unit, a display controller,a digital signal processor, and a memory.
 20. A device comprising theapparatus of claim
 16. 21. The device of claim 20, wherein the device isa battery operated device.
 22. The device of claim 21, wherein thedevice comprises a wireless communication device.